Can conveying carriages which convey spinning cans, receive several full spinning cans at fiber-sliver producing machines, e.g. draw frames, and convey them to a fiber sliver processing machine are known in spinning operations. The conveying carriages are designed so that they can be positioned at the can discharge location of the fiber sliver producing machine and are able to receive pushed-out cans. The reception is effected in that the can pushed out by the machine is pushed on the conveying carriage and pushes the cans already in place thereon farther by one position. Near the end of the conveying carriage, a signal transmitter is installed on the floor of the spinning shop to signal the machine when a can comes within its range. The signal causes the machine to interrupt the filling of additional spinning cans with fiber sliver since no more capacity is left on the conveying carriage. It is a disadvantage in this device that the signal transmitter is mounted on a rod next to the machine. This rod causes injuries to operators or may be damaged by fork lifts, for example, which circulate in the spinning mill.